Jets head coach Todd Bowles likes to rationalize any defensive breakdowns as miscommunication rather than what they really appear to be — blown coverages via mental mistakes. So, judging by the plethora of big plays allowed by Gang Green this season, Bowles’ squad definitely has a failure to communicate.

When the Jets (4-9) host the Dolphins (8-5) in Saturday night’s stand-alone prime-time affair, they’ll only be doing so in a spoiler’s role, as New York’s postseason hopes were realistically dashed weeks ago and Miami is on the cusp of earning a wild-card spot in the AFC.

The Dolphins will be without starting quarterback Ryan Tannehill, though, as he’s out with sprained knee ligaments. Perhaps the exclusion of Tannehill, who started the first 77 games of his career before suffering a left knee injury last week against the Arizona Cardinals, is just what the struggling Jets’ secondary needs. New York has the 22nd-ranked pass defense (253 yards allowed per game), so it could use all the help it can get. Veteran Matt Moore will take the reins and hope to steer clear of disastrous mistakes that could reignite a Jets’ defense that’s taken a beating in recent weeks. Look for first-year Dolphins head coach Adam Gase to not be as creative and daring in the passing game and call a more conservative gameplan, especially if running back Jay Ajayi has early success.

Moore has attempted just 35 passes since the start of the 2012 season — and the bulk of those also came against the Jets on Oct. 28, 2012, when Tannehill suffered knee and quad injuries. Moore, who went 11-of-19 for 131 yards and a touchdown in that 30-9 Dolphins’ win, always seems to have his opportunities intersect with the Jets, so this won’t be unfamiliar territory for the veteran.

It’ll be a battle of backups, Saturday night (NBC, 8 p.m.), as the Jets try to even the season series — and more importantly, put a huge dent in the Dolphins’ playoff hopes.

Metro takes a look at other key story lines to watch, as the Jets and Dolphins renew what is usually a fun and competitive rivalry.

1. Give them some Moore

As Tannehill nurses his damaged knee ligaments, the weight of the Dolphins’ passing game rests on the career backup Moore. The veteran hasn’t started a game in five seasons, but for ardent Jets fans, they’ll remember it vividly — a 19-17 Dolphins win over Gang Green. Moore (22-of-32 for 135 yards, one touchdown and two interceptions) wasn’t great by any measure on that 2012 New Year’s Day matchup, but what he is for Miami is a calming influence and a backup who has the utmost respect of the locker room. His teammates will play for him, judging by the way the offense responded in last week’s comeback win, and especially with the postseason so close they can taste it. Moore went 3-of-5 for 47 yards and directed the game-winning drive against the Cardinals, so the team heads to MetLife Stadium confident he can string together a good performance despite minimal reps all season. Moore is a pro’s pro that the Dolphins shouldn’t panic over inserting into the starting lineup.

2. Heavy run load

Moore needs to be efficient in the passing game, but if Gase loses any faith in him early, look for the Dolphins to employ a run-heavy attack led by Ajayi. The former Boise State star began the season in Gase’s doghouse, but following a surprising early season retirement of Arian Foster, Ajayi has now become Miami’s lead dog on offense. Ajayi has 956 rushing yards and seven rushing touchdowns on the season, but luckily for the Jets, the Dolphins’ run game has waned a bit in recent weeks. When Ajayi burst out in October with back-to-back 200-yard games, Miami’s offensive line was the healthiest it had been all season. But since his recent struggles, Branden Albert, first-round pick Laremy Tunsil and center Mike Pouncey have all dealt with injuries. Ajayi has averaged less than 80 yards per game in each of his past five contests, with fewer than 3.1 yards per carry in two of the last three games. And the Jets had success in pass defense the last time these teams met in Week 9, holding Tannehill and company to less than 200 passing yards, so Saturday night could be the perfect storm for Gang Green if they can duplicate its pass defense success, while also aiding Ajayi in continuing his recent slump. Ajayi had 111 rushing yards and a touchdown in the Miami win the last time they faced off, so it’ll be important for Gang Green to not allow the burgeoning runner to gain traction early.

3. Is Petty ready for a repeat performance?

The second-year quarterback got better as the game went on, last week in San Francisco. Down 17-3 at the half, it was Petty who led the Jets all the way back and forced overtime, as New York stole one at Levi’s Stadium. Petty went 23-of-35 with 257 yards and an interception against the Niners, but it was how he played down the stretch when he engineered a game-tying drive to send the game into overtime and then his game-winning jaunt that led the Jets to the walk-off win that gives hope. It won’t be easy because New York’s passing game has been unreliable for a majority of the season. And even with a Miami secondary that’s been banged up, the Dolphins rank sixth in the NFL with 13 interceptions, while Jets’ quarterbacks have tossed a league-high 19. Petty has thrown four so far during two full starts and two relief appearances and sports a 65.6 rating. Those numbers aren’t stellar, but with his confidence seemingly growing and the Dolphins allowing 234 yards per game through the air, the Jets are hoping their young signal caller can begin to ascend.